How do I offset the scaling center for a cube

I've tried moving down the Center Y value, but this doesn't do it. How can I move the transform center of an object?

Thanks

From the Game Object menu choose Create Empty. In the Hierarchy panel drag the cube you want to scale over the Empty object you created. This will make your cube a child of your Empty object.

Select the cube and adjust its position. Select the parent object and see if your transform gizmo is where you need it. If not, select your cube again and refine your position adjustment until you are happy with it. Then select the parent object and scale it.

Take care that you have to choose Pivot instead of Center (the button immediately to the right of the scale button in the editor).